Nuclear Theory·nucl-th

Monday·April 26, 2021

7 papers—3 primary·4 cross-listed

01
[Submitted on 23 Apr 2021]
Correspondence between momentum dependent relaxation time and field redefinition of relativistic hydrodynamic theory
Sukanya Mitra🇮🇳
In this article a correspondence has been established between the out of equilibrium system dissipation and the thermodynamic field redefinition of the macroscopic variables through the momentum dependent relaxation time approximation (MDRTA) solution of relativistic transport equation. Here, it has been shown that the out of equilibrium thermodynamic fields are not uniquely defined and are subjected to include dissipative effects from the medium. A second order relativistic hydrodynamic theory has been developed including such dissipative effects. The necessary conditions for developing a hydrodynamic theory has been fulfilled, (i) the thermodynamic identities incorporating such redefined fields have been shown to conserve the energy-momentum tensor perfectly under MDRTA, (ii) the non-negativity of entropy production remains unaffected by the inclusion of such dissipative contributions in hydro fields as long as the independent transport coefficients remain positive.
Comments:
Accepted in Physical Review C
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2104.11380 [pdf]
PRC(2022)·6 citations
02
[Submitted on 23 Apr 2021]
Low-energy dipole excitations in $^{20}$ O with antisymmetrized molecular dynamics
Yuki Shikata🇯🇵 · Yoshiko Kanada-En'yo🇯🇵
Low-energy dipole (LED) excitations in $^{20}$ O were investigated by variation after $K$ -projection of deformation( $β$ )-constraint antisymmetrized molecular dynamics combined with the generator coordinate method. We obtained two LED states, namely, the $1_{1}^{-}$ state with one-proton excitation on the relatively weak deformation and the $1_{2}^{-}$ state with a parity asymmetric structure of the normal deformation. The former is characterized by a toroidal dipole (TD) mode with vortical nuclear current, whereas the latter is associated with a low-energy $E 1$ mode caused by surface neutron oscillation along the prolate deformation. The TD (vortical) and $E 1$ modes separately appear as the $K^{π} = 1^{-}$ and $K^{π} = 0^{-}$ components of the deformed states, respectively, but couple with each other in the $1_{1}^{-}$ and $1_{2}^{-}$ states of $^{20}$ O because of $K$ -mixing, and shape fluctuation. As a result of the mixing, TD and $E 1$ transition strengths are fragmented into the $1_{1}^{-}$ and $1_{2}^{-}$ states. We also obtained the $K^{π} = 0^{+}$ , $K^{π} = 0^{-}$ , and $K^{π} = 1^{-}$ bands with cluster structures in the energy region higher than the LED states.
Comments:
12 pages, 15 figures
Subjects:
Nuclear Theory (nucl-th)
arXiv:
2104.11400 [pdf]
PRC(2021)·1 citation
03
[Submitted on 23 Apr 2021]
Intermittency analysis of proton numbers in heavy-ion collisions at energies available at the BNL Relativistic Heavy Ion Collider
Jin Wu🇨🇳 · Yufu Lin🇨🇳 · Zhiming Li🇨🇳 · Xiaofeng Luo🇨🇳 · Yuanfang Wu🇨🇳
Local density fluctuations near the QCD critical point has been suggested to exhibit a power-law behavior which can be probed by an intermittency analysis on scaled factorial moment (SFM) in relativistic heavy-ion collisions. The collision energy and centrality dependence of the second-order SFMs are systematically investigated in Au $+$ Au collisions at $s_{N N}$ = 7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV within the UrQMD model. We estimate the noncritical background in the measurement of intermittency and propose a cumulative variable method to effectively remove the background contributions. We further study the effect of particle detection efficiency by implementing the RHIC (STAR) experimental tracking efficiencies in the UrQMD events. A cell-by-cell method is proposed for experimental application of efficiency corrections on SFM. This work can provide a guidance of background subtraction and efficiency correction for the experimental measurement of intermittency in the search of the QCD critical point in heavy-ion collisions.
Comments:
Replaced with the published version
Subjects:
Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
arXiv:
2104.11524 [pdf]
PRC(2021)·20 citations

Affiliations

first authorsco-authorsvia INSPIRE

Correspondence between momentum dependent relaxation time and field redefinition of relativistic hydrodynamic theory

Low-energy dipole excitations in 20O with antisymmetrized molecular dynamics

Intermittency analysis of proton numbers in heavy-ion collisions at energies available at the BNL Relativistic Heavy Ion Collider

Affiliations

Low-energy dipole excitations in $^{20}$ O with antisymmetrized molecular dynamics